Department of Chemical and Biochemical Engineering and Center for Biocatalysis and Bioprocessing, University of Iowa, Iowa City, Iowa 52242, USA.
Biotechnol Bioeng. 1991 Mar 25;37(7):639-46. doi: 10.1002/bit.260370706.
A variety of enzymes have been found to acylate sucrose in anhydrous pyridine. The enzymic reaction is highly selective; with trifluoroethylbutyrate as ester donor, enzyme-catalyzed transesterification of sucrose yielded sucrose 1'-butyrate and sucrose 6, 1'-dibutyrate. No sucrose-tributyrates were formed. Using a similar technique, a long-chain linear sucrose polyester has been prepared using Proleather, an alkaline protease from a Bacillus sp. This protease catalyzes the esterification of sucrose with bis(2, 2, 2-trifluoroethyladipate) in a 1:1 ratio to yield a sucrose-containing polyester with M(w) = 2100 and M(n) = 1600 for a polydispersity of 1. 31. Polymers with molecular weights in excess of 13, 000 have been prepared by this enzymic approach, indicating that molecules containing over 30 sucrose units have been produced. The polyester is extremely water soluble and soluble in polar organic solvents. As with the sucrose dibutyrate, the polyester has ester linkages at the C6 and C1' positions on the sucrose. The polyester can be depolymerized using Proleather in aqueous buffer, pH7. After 9 days in aqueous buffer, Proleather catalyzed the breakdown of the polyester to an M(w) of ca. 900. This sucrose-containing polyester may have applications as a water-absorbent, biodegradable plastic for use as diapers and hygienic products, water-treatment chemicals, and components of drug delivery systems.
已发现多种酶可使无水吡啶中的蔗糖发生酰化反应。该酶促反应具有高度选择性；以三氟乙基丁酸酯作为酯供体，酶催化蔗糖的酯交换反应生成蔗糖 1'-丁酸酯和蔗糖 6,1'-二丁酸酯。未形成蔗糖三丁酸酯。使用类似的技术，使用来自芽孢杆菌属的碱性蛋白酶 Proleather 制备了长链线性蔗糖聚酯。该蛋白酶催化蔗糖与双（2,2,2-三氟乙基己二酸酯）以 1:1 的摩尔比进行酯化反应，生成一种含蔗糖的聚酯，Mw = 2100，Mn = 1600，多分散性为 1.31。通过这种酶法途径已制备出分子量超过 13,000 的聚合物，表明已生成含有超过 30 个蔗糖单元的分子。该聚酯具有极高的水溶性和在极性有机溶剂中的溶解性。与蔗糖二丁酸酯一样，聚酯在蔗糖的 C6 和 C1'位置具有酯键。聚酯可以在 Proleather 的水性缓冲液中进行解聚，pH 值为 7。在水性缓冲液中 9 天后，Proleather 催化聚酯分解为约 900 的分子量。这种含蔗糖的聚酯可用作吸水性、可生物降解的塑料，用于尿布和卫生产品、水处理化学品以及药物输送系统的组成部分。
